Composite multi-layer substrate and module using the substrate

ABSTRACT

A composite multi-layer substrate comprising a flat plate-like core member formed of a material having an excellent electric conductivity, an excellent heat conductivity, and a high rigidity, a front resin layer and a rear resin layer covering at least the front and rear surfaces of the core member, and a bottomless hole formed in the core member through the front and rear sides of the core member, wherein an electronic component is installed in the bottomless hole, whereby since the strength of the composite multi-layer substrate can be assured by the rigidity of the core member, conventional prior art glass cloth can be eliminated, deterioration in the electric characteristics caused by ion migration can be avoided and will result in reduced production cost.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a composite multi-layer substrate and moduleusing a substrate designed to make high density mounting of electroniccomponents feasible.

2. Description of the Prior Art

Conventionally, package miniaturization has been vigorously carried outas the approach for high density mounting of electronic components. Forexample, recently the Chip Size Package (CSP) and ultimately bare chipmounting which makes the package itself redundant have been realized.However, each of these is premised on arranging and mounting (flatsurface mounting method) a plurality of electronic components in atwo-dimensional (surface) array. By simple calculation, the fundamentallimitation of not being able to reduce the mounting surface areas toless than the size of the added area of each electronic component isretained.

Therefore, a mounting method using embedded mounting of the electroniccomponents in a substrate (more specifically, not only the substrateface) but also the inner section of the substrate attracts attention.

Hereafter, widely known technologies of embedded mounting and theirassociated drawbacks will be explained.

<<Four Prior Art Examples>>

As an electronic component embedded structure using an organic systemsubstrate, the electronic components are mounted in the front surface ofthe organic substrate serving as the core (hereinafter “coresubstrate”). In the case of multi-layering, a structure whichencapsulates electronic components in a dielectric (nonconductive)prepreg resin is known (hereinafter “first prior art example”).Furthermore, a structure in which grooves are formed in an organicsystem substrate wherein electronic components are embedded is known(hereinafter “second prior art example”).

Furthermore, as for mounting electronic components on the front surfaceof a core substrate, a structure (hereinafter “third prior art example”)in which holes corresponding to the size of electronic components aredrilled in the prepreg and the electronic components are inserted andembedded in the holes of the prepreg when multi-layering or a structure(hereinafter “fourth prior art example”) with embedded sinteredcomponents by transfer in organic resin are known.

However, the first prior art example and the fourth prior art examplehave a drawback of being disadvantageous to thin-sizing the substrate.Also, in the second prior art example and the third prior art example,there is a drawback mentioned which involves the processing cost of thegrooves or holes. Moreover, because electronic component heatdissipation countermeasures are not entirely taken into consideration,any of the prior art examples (first through fourth prior art examples)have a drawback causing inconvenience in mounting electronic componentsespecially in regard to heat generation in larger semiconductor chips,etc.

<<Fifth Prior Art Examples>>

Japanese Laid-Open Patent Application (Kokai) (A) No. S54-008871 (1979)titled “SEMICONDUCTOR DEVICE” discloses that in order to provide a solidelectronic clock that is thin-shaped and a small size, while forming apattern in one side of a printed circuit board, the device is made of aprinted circuit board and a semiconductor chip of almost the equivalentthickness by adhering a metal plate to the rear surface, forming a“hole” in one or both directions in the pattern or metal plate andmounting a semiconductor chip in the hole. However, by this prior artexample, when performing a resin seal of the semiconductor chip andmulti-layering, there is a drawback of having to grind off the excessresin requiring additional work and making manufacturing costs moreexpensive. Additionally, concerning mounting in a hole and electroniccomponent having multiple electrodes, such as the five-sided electrode,etc., there is a drawback that the type of electronic component whichcan be mounted has limitations and this constitution was not taken intoconsideration at all.

<<Sixth Prior Art Example>>

Japanese Laid-Open Patent Application (Kokai) (A) No. S61-287194 (1986)titled “CHIP CARRIER FOR USE IN ELECTRONIC DEVICES” discloses elevationof the heat dissipation effect in electronic components. An insulatingresin is laminated on a metal core front surface of a printed circuitboard with a metal core base. While forming “concave portions” whichreach to the metal core of that insulating resin, the device uses themetal core as a heat sink by mounting in the concave portions in orderfor the rear surface of an electronic component to be in contact to themetal core. This prior art example describes concave portions that areformed so the insulating resin laminated to the metal core rear surface(opposite side of the mounting surface of the electronic components)also reaches the metal core and the heat dissipation effect is elevated.

<<Seventh Prior Art Example>>

Japanese Laid-Open Patent Application (Kokai) (A) No. S64-011400 (1989)titled “MULTILAYERED PLATE FOR MOUNTING IC CHIP” discloses a means todissipate the heat of semiconductor chips from adjacent positions and toprovide a multi-layer substrate for mounting semiconductor chips withoutgenerating improper bonding with the metal plate for heat dissipation byway of “holes” for semiconductor chip mounting formed in metal foil or ametal sheet. A printed circuit board is used in which the wiring networkcontaining the above-mentioned holes are formed in one side or bothsides of a metal base copper clad laminate in which prepreg or copperfoil is superimposed. However, in this prior art example, therelationship between the metal foil in the side walls of the holes formounting semiconductor chips or the height of the metal sheet and thethickness of the semiconductor chips is not defined. In addition, theconfiguration having taken into consideration heat dissipation of thesemiconductor chips is not defined. Further, from the depth relationshipof the holes for mounting semiconductor chips and the thickness of thesemiconductor chips not being clear, consideration of thin-sizing isregarded to be insufficient. Also, from having to remove the glass cloth(described later) when the holes for mounting semiconductor chips in aprinted circuit board are formed, the increased manufacturing cost isreadily anticipated.

<<Eighth Prior Art Example>>

Japanese Laid-Open Patent Application (Kokai) (A) No. S64-012598 (1989)titled “IC CHIP MOUNTING MULTILAYER BOARD” discloses the use of a metalsheet with a thickness of 0.1˜1.0 mm, preferably 0.2˜0.5 mm, and with athermal expansion coefficient of not more than 9×10⁻⁶ cm/cm/° C.Although performing surface treatment suitably and improving theadhesive property is mentioned, these can also be considered similarproblems (namely, consideration of thin-shaping is insufficient andincreased manufacturing cost) relative to the seventh prior art example.

<<Ninth Prior Art Example>>

Japanese Laid-Open Patent Application (Kokai) (A) No. H02-122534 (1990)titled “HYBRID INTEGRATED CIRCUIT” discloses a means to provide a hybridintegrated circuit in which high current can flow and miniaturized highdensity mounting is made possible. The wiring pattern is formed with“openings” for mounting semiconductor chips in a thermoplastic resinplate, and further consists of semiconductor chips and a metal plate ofthe same thickness arranged on either side of the semiconductor chips.Also, the thermoplastic resin plate in which the wiring layer is formedin a multi-layer is united with another thermoplastic resin plate bymeans of thermocompression bonding. The lead terminals of thesemiconductor chips are inserted in the openings provided between thethermoplastic resin plates formed in the multi-layer wiring layer andelectrically connects with the wiring layer. However, in this prior artexample, the measures relative to heat dissipation of the semiconductorchips are not clear. Also, the resin seal around the circumference ofthe semiconductor chips is problematic from thermocompression bondingwith the thermoplastic resin plates in which the openings are formed andthe thermoplastic resin plates with which the multi-layer wiring layeris formed. When thermocompression bonding is performed in the state offusing the thermoplastic resin plates, fluctuation of the thicknessbetween layers of the section which forms the multi-layer wiring layercan be anticipated, and electrical specification control can be presumedto be difficult.

<<Tenth Prior Art Example>>

Japanese Laid-Open Patent Application (Kokai) (A) No. 2002-111226 titled“COMPOSITE MULTILAYER BOARD AND MODULE FOR USING IT” disclosure isexplained below.

FIG. 12A is a cross sectional plan view of the composite multi-layersubstrate described in the official gazette. This composite multi-layersubstrate 1 has a stacked multi-layer structure of a plurality oflayers. The illustrated example has four layers (described later “resinlayers”) 2˜5 which are composed of resin material. These resin layers2˜5 are common in that all use resin materials, such as epoxy, etc., forthe material (so-called glass cloth 7) and only the layer of the resinlayer 2 (drawing top layer) is different in the respect that a glassfiber 6 is contained within the braided (knitted) shape of a net asshown in FIG. 12B. The glass cloth 7 is reinforcement for enhancing thephysical strength of the composite multi-layer substrate 1. Forconvenience of explanation hereinafter, while the resin layer 2 which“has” the glass cloth 7 is denoted as “glass cloth layer 2,” the resinlayers 3˜5 which do not have, the glass cloth 7 are denoted as “glassclothless layers 3˜5.”

Further, this composite multi-layer substrate 1 is bonded to copper foilon the bottom most surface (underside of the glass clothless layer 5) asthe mounting side. The conductor pattern of copper foil is created byetching techniques, and the conductor pattern 8 of the required shape isformed. Also, some of the glass cloth layer 2 is eliminated wherein aconcavity 9 (It is called a mold cavity whereas an opening is generallyclosed.) is formed and the electronic components 10 (for example,semiconductor chips) are mounted in the concavity 9.

The electronic components 10 “are embedded” by using the inner sectionof the composite multi-layer substrate 1. Accordingly, other componentscan be mounted to the composite multi-layer substrate 1 front surfacealong with components mounted in higher density.

However, since the invention described in the above-mentioned officialgazette (tenth prior art example) uses the glass cloth 7 asreinforcement for enhancing the physical strength of the compositemulti-layer substrate 1:

(1) There is a problem of ion migration occurring relative to theinterface of the glass fiber 6 and the resin (the main material of theglass cloth layer 2), whereby the insulation becomes destroyed dependingon the intensity of the electrolysis and resultant deterioration in theelectrical properties.

(2) In order to form the concavity 9 for the mold cavity, it isnecessary to physically remove some of the resin layer 2. In that case,the glass fiber 6 within the resin layer 2 must be severed. Althoughsuch a cutting operation commonly uses precision processing machines,such as laser, etc., truncation errors are undeniable and considerableproduction time is also required. Moreover, when a plurality of theconcavity 9 is required, there is a problem that the production timeproportionately increases which incurs higher manufacturing costs.

Therefore, the present invention's purpose is to prevent deteriorationof the electrical characteristic accompanying the generation ofmigration and aiming at reduction of the manufacturing cost by usingother reinforcement as a substitute for the glass cloth.

SUMMARY OF THE INVENTION

The present invention has been made in view of the conventional priorart drawbacks mentioned above. The present invention is constituted witha composite multi-layer substrate comprising a flat plate-like coremember formed of a material having excellent electric conductivity,excellent heat conductivity and high rigidity; a front side resin layerand a rear side resin layer covering at least a front surface and a rearsurface of the core member; and a bottomless hole formed in the coremember penetrates the front and rear of the core member, wherein anelectronic component is mounted in the bottomless hole.

Further, the present invention is constituted with a compositemulti-layer substrate comprising a flat plate-like core member formed ofa material having excellent electrical conductivity, excellent heatconductivity and high rigidity; a front side resin layer and a rear sideresin layer covering at least a front surface and a rear surface of thecore member; and a flat bottomed hole formed in the core member openingin either the front surface side or rear surface side of the core memberwherein an electronic component is mounted in the flat bottomed hole.

Here, the present invention is not limited in particular. What isessential is just to have a combination of the three above-statedproperties: “material which has excellent electrical conductivity,excellent heat conductivity and high rigidity.”

According to the present invention, as the core member consists of“material which has excellent electrical conductivity, excellent heatconductivity and high rigidity,” typically, a core member made frommetal (metallic) is preferred, but copper, Alloy 42, Invar, etc. areparticularly preferred.

Additionally, though each “bottomless hole” and “bottomed hole” are usedto mount an electronic component (an electronic component is a generalterm of a passive component part, such as a semiconductor chip, atransistor, a resistance element, a capacitative element, an inductanceelement or other electronic components), the first is different in termsof a “a hole without a bottom (or a through hole)” and the latter “ahole with a bottom (or a concave portion)”. Also, the opening shape of a“bottomless hole” and a “bottomed hole” should just have an appropriateshape (for example, a little higher shape than the outside of theelectronic component) which can conveniently mount a target electroniccomponent.

In a composite multi-layer substrate which has these characteristics, inorder to have a core member which has rigidity, it is not necessary touse glass cloth as a reinforcing material. Therefore, various kinds ofinconveniences (namely, aggravation of electrical properties by anaccompanying generation of ion migration and the increased manufacturingcost accompanying the glass cloth cutting process) which accompany glasscloth are avoided.

According to the present invention, the composite multi-layer substratefurther comprises a side surface resin material which covers the sidesurfaces of the core member; and the core member is entirely covered bythe side surface resin material, the front side resin layer and the rearside resin is layer.

According to the present invention, the composite multi-layer substratecomprises a column segment which divides the structure of the coremember and penetrates the front and rear surfaces in the thicknessdirection of the core member; and the column segment is used as part ofthe electrical signal transmission path or power supply voltagetransmission path to the direction of the front and rear surfaces of thesubstrate.

According to the present invention in the composite multi-layersubstrate, the core member is used as a heat dissipation path of anelectronic component through the inner wall of the bottomless hole orthe flat bottomed hole when an electronic component is mounted in thebottomless hole or the flat bottomed hole.

According to the present invention, the composite multi-layer substratewherein the upper surface height position of an electronic componentafter mounting in the bottomless hole or the bottomed hole, at least,does not cross the upper surface height position of the core member.

According to the present invention, the composite multi-layer substratewherein a height size adjustment member is interposed between the bottomof an electronic component when an electronic component height size islower than the depth size of the core member mounted in the bottomlesshole; and the height size adjustment member performs mounting heightadjustment of an electronic component.

According to the present invention, the composite multi-layer substratewherein the height size adjustment member constitutes material which hasheat conductivity.

According to the present invention, a module is constituted using thecomposite multi-layer substrate.

The above and further objects and novel features of the presentinvention will more fully appear from the following detailed descriptionwhen the same is read in conjunction with the accompanying drawings. Itis to be expressly understood, however, that the drawings are for thepurpose of illustration only and are not intended as a definition of thelimits of the invention.

BRIEF DESCRIPTION OF TEE DRAWINGS

FIGS. 1A˜1C are main cross sectional plan views and a main perspectiveview of a composite multi-layer substrate in the embodiment;

FIGS. 2A and 2B are composition diagrams when mounting an electroniccomponent 25 in a bottomless hole 24 of the core member 21;

FIGS. 3A and 3B are composition diagrams when mounting an electroniccomponent 25 in a bottomless hole 24 of the core member 21;

FIGS. 4A and 4B is a main cross sectional plan view in another sectionof the core member 21 and an external perspective view of the section;

FIG. 5 is a cross sectional plan view of a module 40 applied to thepresent invention;

FIGS. 6A˜6C are manufacturing process diagrams (first through thirdprocesses) of a module 40;

FIGS. 7A and 7B are outline views after the third process;

FIGS. 8A˜8C are manufacturing process diagrams (fourth through sixthprocess) of a module 40;

FIGS. 9A and 9B are outline views after the fifth and sixth processes;

FIGS. 10A˜10D are manufacturing process diagrams (seventh through tenthprocesses) of a module 40;

FIGS. 11A and 11B are outline views after the tenth process; and

FIGS. 12A and 12B show a cross sectional plan view of a conventionalprior art composite multi-layer substrate and an enlarged plan view ofthe glass cloth.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, the embodiments of the present invention will be explainedwith reference to the drawings.

First Embodiment

FIGS. 1A˜1C are main cross sectional plan views and a main perspectiveview of a composite multi-layer substrate in the form of the embodiment.In this cross sectional view, the composite multi-layer substrate 20 hasa “multi-layer structure.” Referring to the example illustration, thecomposite multi-layer substrate 20 has a three-layer structurecomprising a core member 21, a resin layer 22 (hereinafter “substratefront side resin layer”) and a resin layer 23 (hereinafter “substraterear side resin layer.” The core member 21 in the shape of a flatplate-like board is composed of a material which has excellentelectrical conductivity, excellent heat conductivity and high rigidity.The substrate front side resin layer 22 covers the front surface of thecore member 21 (in the direction of the drawing, the upper surface). Thesubstrate rear side resin layer 23 covers the rear surface of the coremember 21 (in the direction of the drawing, the lower surface).

The essential physical characteristics for the core member 21 are theabove-mentioned three: excellent electrical conductivity, excellent heatconductivity and high rigidity. “Excellent electrical conductivity”pertains to the property of a material that allows electricity to passthrough easily (that is, electrical resistance is low). “Excellentthermal conductivity” pertains to the ability to convey heat easily(that is, thermal conductivity is high). “High rigidity” pertains tominimal stress deformations due to bending or compressing. Theconstruction material is not limited. What is essential is just to havethe above-mentioned physical characteristics. Typically, metal(metallic) is preferred and especially more preferable when metals suchas Cu (copper), Alloy 42, Invar, etc., are used which simultaneouslysatisfy the above-mentioned three physical characteristics.

Additionally, the material of the resin layers (the substrate front sideresin layer 22 and the substrate rear side resin layer 23) covering thefront and rear of the core member 21 has electrical insulating andenvironmental capabilities (water resistant, acid resistant, etc.), andif required further has the necessary dielectric constant. An insulatingmaterial, for example, such as epoxy, polyimide, cyanate ester, Teflon(registered trademark), etc., used for a resin material or printedcircuit boards can be used.

A through hole 24 (hereinafter “bottomless hole”) of predeterminedopening shape is formed in the core member 21 and penetrates the frontand rear (refer to FIGS. 1A and 1B). The bottomless hole 24 is used as amounting hole of an electronic component 25. Hence, an electroniccomponent 25 is mounted (embedded) in the inner part of the compositemulti-layer substrate 20 and improvement of high density packaging canbe achieved.

According to the composite multi-layer substrate 20 which has such astructure, physical strength (flexural rigidity, etc.) of the compositemulti-layer substrate 20 can be acquired with the rigidity of the coremember 21. Therefore, the reinforcing material (glass cloth 7; refer toFIG. 12) used in the past can be made redundant and variousinconveniences related to the application of the glass cloth can beavoided.

Namely, as the core member 21 which has “high rigidity” at least usesother reinforcement material which replaces the glass cloth, the problemof ion migration explained earlier [Ion migration occurs relative to theinterface of the glass fiber 6 front surface and the resin, whereby theinsulation becomes destroyed and the electrical characteristic isdeteriorated.]; and the problem of increased manufacturing cost [Inorder to form a bottomed hole 9 for a cavity, it is necessary tophysically remove a portion of the resin layer 2. In that case, eventhough the inner part glass fiber 6 of resin layer 2 must be severed andsuch a cutting operation uses a precision processing apparatus, forexample generally a laser, etc., a truncation error cannot be denied andconsiderable work hours are required. Moreover, when a plurality of thebottomed hole 9 is necessary, the number of needed work hours onlyredoubles which causes a rise in manufacturing cost.] can be solved.Thus, the ultimate objects of the present invention (to avoiddeterioration of the electrical characteristic accompanying generationof migration and to cutback the manufacturing cost) can be achieved.

In addition, although the above explanation showed an example ofmounting an electronic component 25 in the bottomless hole 24 formed inthe core member 21, an electronic component mounting hole does notnecessarily have to be a hole (namely, a bottomless hole) which“penetrates front and rear.” For example, as shown in FIG. 1C, a concaveportion 26 (hereinafter “flat bottomed hole”) may be formed in the coremember 21 and an electronic component 25 can be mounted in a bottomedhole 26. In this manner, by direct contact or via heat conductiveadhesive, etc. between an electronic component 25 and the base of a flatbottomed hole 26, etc., the heat generated by an electronic component 25can efficiently escape to the core member 21. Thus, the core member 21can be used for heat dissipation of an electronic component 25.

Also, it is desirable to presume that the resin layer structure(selection, thickness, etc.) for the front and rear surface sides of thecore member 21 be approximately the same. The composite multi-layersubstrate 20 front and rear surfaces are made into a symmetricalstructure. Because the resin layers on the front and rear surface sides(front side resin layer 22 and rear side resin layer 23) of the coremember 21 lessen differential thermal expansion, “curvature” of thecomposite multi-layer substrate 20 can be controlled.

As stated above, even though the front and rear surface sides of thecore member 21 are each covered by the front side resin layer 22 and therear side resin layer 23, it is desirable when the sides of the coremember 21 are also covered by resin, etc. That is, it is desirable tocompletely enclose (sealant or coating) “all the surfaces” of the coremember 21 with an environmentally resistant material equivalent to resinor thereto. Since the front and rear surfaces of the core member 21 eachcovered by the front side resin layer 22 and the rear side resin layer23 are not unprotected to ambient air, there is no concern aboutoxidation. However, when the sides of the core member 21 are exposed,there is a possibility that the surfaces may oxidize gradually andgenerate an electrical short circuit, etc. causing a malfunction betweenthe mounted components adjoining this exposure.

Second Embodiment

FIGS. 2A and 2B are composition diagrams when mounting an electroniccomponent 25 in a bottomless hole 24 of the core member 21. Referring toFIG. 2A, when the upper surface height position of the core member 21 isassumed to be La and the upper surface height position of an electroniccomponent 25 is assumed to be Lb, as for the differential d (d=La−Lb) ofthe height, it is desirable to formulate a value of zero or more thanzero (namely, La=Lb or any relation of La>Lb). In this manner, since theupper surface height position La of the core member 21 constitutes aposition always higher than the upper surface height position Lb of anelectronic component 25, it can respond to the loading (load added whenthe front side resin layer 22, etc. is laminated) to an electroniccomponent 25 on the core member 21 at the time of manufacturing thecomposite multi-layer substrate 20 and damage to an electronic component25 is avoidable.

FIG. 2B is a composition diagram when mounting the electronic component25 in a bottomless hole 24 of the core member 21. The variation in FIG.2B places a thermally conductive resin 28 interposed between anelectronic component 25 and the rear side layer 23 which are in contactwith a side edge of the thermally conductive resin to the internalsurface of a bottomless hole 24 of the core member 21. In this manner,the heat generated by an electronic component 25 can be dissipatedefficiently to the core member 21 from the internal surface of abottomless hole 24 via the thermally conductive resin 28.

Furthermore, FIG. 3A is a composition diagram when mounting anelectronic component 25 in a bottomless hole 24 of the core member 21.The variation in FIG. 3A places a bottomless hole 29 also in the rearside resin layer 23 loaded with a height size adjustment member 30 whichconstitutes two bottomless holes 24, 29 from good thermally conductivematerial (for example, copper, etc.) and an electronic component 25 isplaced and mounted on this height size adjustment member 30.

Here, when calculating the depth size Ha of the core member 21, theheight size Hb of the resin side layer 23 and the height size Hc of theheight size adjustment member 30, in order to adjust the differential dof the height of the upper surface position La of the core member 21 andthe upper surface height position Lb of an electronic component 25 tothe desired value, it only has to satisfy the relation of:Ha+Hb=Hc+Hd+d  (1)because Ha, Hb and Hc are fixed values. For example, in order to maked=0:Ha+H=Hc+Hd  (2)Therefore, height Hd of the height size adjustment member 30 is suitableas:Hd=Ha+Hb−Hc  (3)

Based on this, even if it is a case that the height size Hc of anelectronic component 25 is extremely small as compared with the depthsize Ha of the core member 21, the above-stated size differential d canbe readily set to a desired value and various electronic components withdifferent height sizes can be conveniently embedded in the compositemulti-layer substrate 20. Also, if good thermally conductive material isused as the height size adjustment member 30, heat generated by anelectronic component 25 can be dissipated from the height sizeadjustment member 30 to the core member 21 via the internal surface of abottomless hole 29. Further, heat can be dissipated also to the exteriorfrom the underside of the height size adjustment member 30 and the heatdissipation effect of an electronic component 25 can be improved muchmore.

FIG. 3B is a composition diagram when mounting an electronic component25 in a bottomless hole 24 of the core member 21. The variation in FIG.3B makes it possible to apply an electronic component 25 with a largeheight size. Referring to FIG. 3B, the height size Hc of an electroniccomponent 25 exceeds the depth size Ha of the core member 21 (Ha<Hc).This electronic component 25 is mounted on both sides of a bottomlesshole 24 formed in the core member 21, a bottomless hole is formed in therear side resin layer 23. A portion of the underside of an electroniccomponent 25 and the sides are held via a thermally conductive resin 32in two holes (a bottomless hole 24 and bottomless hole 31).

In this manner, even if an electronic component 25 has a large heightsize, the above-stated size differential d can be readily set as thedesired value. Heat generated by an electronic component 25 can bedissipated from the thermally conductive resin 32 to the core member 21via the internal surface of a bottomless hole and can also be dissipatedfrom the underside of the thermally conductive resin 32 to the exterior.Thus, the heat dissipation effect of an electronic component 25 can beimproved still more.

Third Embodiment

FIGS. 4A and 4B is a main cross sectional plan view in another sectionof the core member 21 and an external perspective view of the section.Referring to these drawings, a column segment 33 is set in an optionalposition (although adjacent to a bottomless hole 24 in the drawing, itis not limited to this) of the core member 21.

The column segment 33 is originally a portion of the core member 21.Specifically, it is a “remaining part” of the core member 21 produced byhaving formed a cylindrical dividing groove 34 in an optional positionof the core member 21. A column segment 33 can be used as follows.Namely, when a via hole 35, 36 is formed in both the front side resinlayer 22 and the rear side resin layer 23 and an electrode 37, 38 isformed in the via hole 35, 36 in both directions of one end side and theother end side of the column segment 33 (island-shaped sections), theelectrode 37, 38 are electrically connected via a column segment 33.Furthermore, because the end face of each of the electrode 31, 38 isexposed to the front and rear surfaces of the composite multi-layersubstrate 20, the electrode 37, 38 and the column segment 33 can be usedas double-sided penetration wiring of the composite multi-layersubstrate 20. Thus, an electrical signal or power supply voltagetransmission path can be obtained.

Fourth Embodiment

FIG. 5 is a cross sectional plan view of a module 40 applied to thepresent invention.

A “module (the United Kingdom: module)” signifies “a standardized unit.”Although a module is interpreted as a type of unit or component, a unitis usually situated as an exchangeable integrant part. A module does notassume replacement parts being situated as a minimum configurationmodule by itself and further is designed and manufactured as anapparatus with a specific function in most cases. However, since inactuality that precise categorization is not defined, in the descriptionit is assumed that this terminology (“module”) is defined as follows.Namely, a module which can be said to comprise one or more (acombination of electronic components of different kinds is included)electronic components (these are named generically and called an“electronic component”) of a semiconductor chip, a resistance element, acapacitative element or others are mounted in the inner sections and anecessary electronic circuit function is actualized, as well as anapparatus which can be distributed individually in the marketplace.Subsequent replacement simplicity including (installing) optionalelectronic devices is not especially considered. It may have a mountingconfiguration which can be attached and detached by a connector, etc.and may be formed mounted mostly in a fixed state by soldering, etc.

A module 40 as shown in FIG. 5, for example, can function as a poweramplifier module which is an integral part of an Radio Frequency (RF;high-frequency wave) section in a portable telephone or a PersonalDigital Assistant (PDA) with a wireless communications device, anantenna switch module or an RF module which unifies these and can bedistributed in the marketplace by itself as a product.

A module 40 actualizes desired circuitry (a power amplifier module, anantenna switch module or an RF module that unified these) by mountingthe necessary electronic components in the front surface and innersection of a composite multi-layer substrate having a structure whichapplies the technical concept of the above-mentioned embodiments (firstthrough third embodiments).

As shown in FIG. 5, the module 40 structure can be roughly divided intoan intermediate layer A, a upper rank layer B laminated to theintermediate layer A upper surface, and a lower rank layer C laminatedto the intermediate layer A lower surface.

The intermediate layer A is laminated to a front side resin layer 42 anda rear side resin layer 43 respectively to both sides of a core member41. A plurality (cross sectional plan view shows four) of bottomlessholes 44˜47 are formed in the core member 41 and has a structureembedded with suitable electronic components 48˜51 for each of thebottomless hole 44˜47.

Next, as an explanation for convenience, assume the electronic component48 on the left end is a semiconductor chip with a short height size, theelectronic component 49 which is second from the left is a capacitor(the height size is the depth size level of the core member 41), theelectronic component 50 which is third from the left is a resistor (theheight size is the depth size level of the core member 41) and theelectronic component 51 is a semiconductor chip with a tall height size.

The electronic component 49, 50 with a height size about the depth sizeof the core member 41 are embedded and mounted in the bottomless hole45, 46 respectively. As stated above, the electronic component 49, 50are a capacitor and a resistor respectively. Since these componentsgenerate relatively little heat, the limitations of particular heatcountermeasures are not required. An adhesive 52, 53 may be filled inbetween the rear side resin layer 43 to perform adhesion of theelectronic component 49, 50. When heat generation of the component issevere, a good heat conductor should be used for the adhesive 52, 53respectively.

Moreover, if it is the electronic component 48 with a short height size,a height size adjustment member 54 is put in and the height size isadjusted. When heat generation of the electronic component 48 is severe,a good heat conductor is used for the material of the height sizeadjustment member 54. Further, if it is the electronic component 51 witha tall height size, the height size is adjusted by embedding so that therear side resin layer can be reached. When heat generation of theelectronic component is severe, the sides and underside of theelectronic component 51 are covered and laminated with a thermallyconductive resin 55. In any case, the height size adjustment member 54and a thermally conductive resin 55 which borders the portion of thecore member 41 and the portion of the base section exposed from theintermediate layer A underside.

Besides, a column segment 56, 57 is set inn optional position of thecore member 41. Also, the column segment 56, 57 constitute signaltransmission paths or power supply transmission paths which penetratethe intermediate layer A front and rear with an electrode 58, 59, 60, 61established so as to connect to both sides. In the intermediate layer A,62˜75 are electrodes.

The lower rank layer C forms an electrode pattern (described later indetail) of the required shape in both sides of a resin layer 76 and theupper rank layer B also forms an electrode pattern (described later indetail) of the required shape in both sides of a resin layer 77. Also,surface mounting of an electronic component 78˜82 is performed on apredetermined electrode pattern. A covering cover 40 a (desirable forfunctioning as electromagnetic shielding for EMI measures) is attachedfor the electronic component 78˜82. Although not limited in particular,the electronic component 78, 79 and 81 is a capacitor and the electroniccomponent 80, 82 is a resistor.

Thus, the module 40 uses a plate-like core member 41 consisting ofmaterial (Cu (copper), Alloy 42, Invar, etc.) having excellentelectrical conductivity, excellent heat conductivity and high rigidity,as well as a structure built up with the resin layers 76, 77 in thefront and rear surfaces of the core member 41. Here, the two resinlayers 76, 77, for example, are both made with a resin, such as epoxy,polyimide, polycyanate ester, Teflon (trademark), etc. as the mainingredients (functional powder, such as dielectric powder and magneticsubstance powder mixed in by desire is also good) or an insulatingmaterial used for a printed circuit board can be used. Thecharacteristic is in the point of view (namely, the point of view whichis a glass cloth less layer) of not having a glass cloth 7 (referring toFIG. 12) explained at the beginning. As the flexural rigidity of themodule 50 is obtained by the core member 41 which mainly has anintermediate layer A base, it does not require the glass cloth 7 asreinforcing material.

The four cavities (those which form the bottomless hole 44˜47) of thecore member 41, a semiconductor chip (electronic component 48, 51), acapacitor (electronic component 49) and a resistor (electronic component50) are each embedded. Then, among those electronic components whichgenerate a large amount of heat (electronic component 48, 51), thebottom portion of each component and side surfaces (when required) areeach connected to the core member 41 via a good thermally conductivematerial (height size adjustment member 54 and thermally conductiveresin 55) and also connected with the upper surface electrode pattern82, 83 of the lower rank layer C. The core member 41 dissipates via theinternal surface of the bottomless holes. Furthermore, an electronicdevice substrate which mounts the module 40 will dissipate heat via theunderside of an electrode pattern 86 of the lower rank layer C. Thus,sufficient heat dissipation can be acquired.

Additionally, as for a semiconductor chip (electronic component 48) witha short height size with the height size adjustment member 54 (Anindependent member or built up with plating. It has excellent heatconductivity and the height size adjustment of the electronic component48 is carried out.) which is placed in a cavity (Those which are formedin the bottomless hole 44 of the core section 41 and a through hole ofthe same position.) formed in the lower rank layer C, it can be raisedto a mounting height in the desired position and the relation (refer tothe relation of La and Lb of FIG. 2) between the upper surface heightposition of the electronic component 48 and the upper surface heightposition of the core member 41 can be maintained appropriately.

As for a semiconductor chip with a tall height size (electroniccomponent 51), the relation (refer to the relation of La and Lb of FIG.2) between the upper surface height position of the electronic component51 and the upper surface height position of the core member 41 can bemaintained appropriately by placing an electronic component into acavity (those which are formed in the bottomless hole 47 of the corepart 41 and a through hole of the same position) formed in the lowerrank layer C.

Patterning (formation of the bottomless hole 44˜47 or the column segment56, 57) in the intermediate layer A of the core member 41 should beperformed in the state where the rear side resin layer 43 emulates theunderside of the core member 41. Because of the “island” shaped sectionswhich are not removed in particular, the sections can be used as thecolumn segment 56, 57 when the core member 41 is patterned in thisstate. Therefore, a columnar structure (what is called a “mailbox”:those which are formed of the electrode 58, 59, 60 and 61 connected withthe column segment 56, 57 to both ends) for connecting the front andrear of the intermediate layer A can be readily formed by physicalprocessing (for example, etching) of the core member 41. When etchingthe core member 41 with a common etchant, such as Ferric Chloride, etc.,the core member 41 material can be made from Cu (copper), Alloy 42,Invar, etc. from a relation of physical properties. However, when Alloy42 and Invar are selected, it is preferred to perform Cu plating to thefront surface of Alloy 42 or Invar from the prevention standpoint of ionmigration, etc.

Next, the manufacturing process of the above-stated module 40 will beexplained.

(First Process: FIG. 6A)

A plate-like core member 41 having excellent electrical conductivity,excellent heat conductivity and high rigidity comprising, a laminatedresin layer (rear side resin layer 43) on the underside (referring tothe upper and lower side directions in the drawing) of core member 41,for example, Cu, Alloy 42 or Invar, etc. and further, a thin film 90having excellent electrical conductivity, excellent heat conductivityand high rigidity on the underside of the rear side resin layer 43 isglued together.

Here, as the material of the rear side resin layer 43, an insulatingmaterial, for example, such as epoxy, polyimide, cyanate ester, Teflon(registered trademark), etc. used for a resin material or printedcircuit boards can be used. Also, as for the thin film 90 having theabove-mentioned characteristics, typically copper foil can be used.

Basically, solutions which unify the rear side resin layer 43 and thethin film 90 may be used. For example, an apparatus which uses copperfoil with resin or copper foil glued together to dry film can be used.

(Second Process: FIG. 6B)

Next, the core member 41 is patterned and the bottomless hole 44˜47 andthe column segment 56, 57 are formed. The bottomless hole 44˜47 eachconstitute a cavity for embedding the electronic component 48˜51.Patterning of the core member 41 can be carried out, for example, byapplying a subtractive process. In this case, an etchant current usedwith ordinary printed circuit boards, such as Ferric Chloride or CupricChloride (acid based) etchant, etc. can be used.

(Third Process: FIG. 6C)

Next, as for the bottomless hole 44, 47 corresponding to the electroniccomponent (electronic component 48, 51) which generate a large amount ofheat, the rear side resin layer 43 underneath is removed in the sameopening shape as the bottomless hole 44, 47 (refer to the dotted linesection) and the thin film 90 is exposed. Removal of the rear side resinlayer 43, for example, can be carried out, for example, by laserabrasion, plasma etching, etc.

FIG. 7 shows outline views after the third process in which FIG. 7Aillustrates the upper surface side perspective view and FIG. 7B is thelower surface side perspective view. Also, FIG. 7 and the above-statedprocess diagrams (FIGS. 6A˜6C) do not strictly correspond. The points ofview that should be understood in FIG. 7 are the “cavities” and the“mailbox” which are formed in the core member 41. Accordingly, as shownin FIGS. 7A and 7B, the resin layer 91 (equivalent to the rear sideresin layer 43 of FIG. 6) and copper foil 92 (equivalent to the thinfilm 90 of FIG. 6) are glued together on the underside of the coremember 41. The core member 41 is patterned with several of the cavity93˜95 (equivalent to the bottomless hole 44˜47 in FIG. 6) and severalmailbox 96˜103 (equivalent to the column segment 56, 57 in FIG. 6) areformed.

(Fourth Process: FIG. 8A)

Next, the height size adjustment member 54 is inserted into thebottomless hole 44 on the left end and thermally conductive resin 104 isapplied to the height size adjustment member 54. Moreover, the adhesive52, 53 is applied to the second and third of the bottomless hole 45, 46from the left and further the thermally conductive resin 55 is appliedto the right end bottomless hole 47. The height size adjustment member54 may be independent (stand-alone) or may be built up with plating,such as Cu, etc. It only has to have excellent heat conductivity and beable to perform height size adjustment of the electronic component 48.As the name suggests, the thermally conductive resin 104, 55 has afunction which performs temporary fastening of the embedded electroniccomponent 48, 51 while also having a heat dissipation effect. Theadhesive 52, 53 only need to have a function which mainly fixes (bonds)the embedded electronic component 49, 50.

Here, although the electronic component 49, 50 which do not requireparticular heat dissipation countermeasures are fixed with the adhesive52, 53, the embodiment is not limited to this. For example, in the caseof the first process (FIG. 6A), lamination is completed whereinnon-hardened sections remain without performing a full cure of the resinlayer when the core member 41 and the resin layer (rear side resin layer43) are glued and laminated. In the case of the electronic component 49,50 mounted in the fourth process (FIG. 8A), it is possible to fix theelectronic component 49, 50 by making each a high temperature case andrecovering some viscosity of the resin layer. When performed in thismanner, the adhesive 52, 53 coating operation can be consideredunnecessary.

(Fifth Process: FIG. 8B)

Next, the electronic component 48˜51 respectively corresponding to eachof the bottomless hole 44˜47 are mounted. As for the first electroniccomponent 48 wherein heat dissipation is necessary, heat can bedissipated to the core member 41 and the thin film 90 via the thermallyconductive resin 104 and the height size adjustment member 54. Also, asfor the second electronic component 51 wherein heat dissipation isnecessary, heat can be dissipated to the core member 41 and the thinfilm 90 via the thermally conductive resin 55.

(Sixth Process: FIG. 8C)

Next, after mounting the electronic component 48˜51, the core member 41is encapsulated by a resin. By means of this sealing, the front sideresin layer 42 in the first through third embodiments is formed and thecrevices surrounding the front surface of the core member 41, cavities(bottomless hole 44˜47) and through mailboxes (column segment 56, 57)are completely covered by the front side resin layer 42. Here, it isdesirable to also encapsulate completely in resin the side edges (referto the dotted line enclosure parts A and B in FIG. 8C) of the coremember 41. As a resin which encapsulates the side edges, although it mayfunction as a portion of the front side resin layer, the side resinlayer may be set in another body with the front side resin layer. Whenproduced in such a manner, all the surfaces of the core member 41 areinsulated from the environmental atmosphere (air) and oxidation of thecore member 41 by oxygen, moisture, etc. in the environment can beprevented. Also, electrical short circuits between adjacent mountedcomponents, etc. is prevented and malfunctioning can be avoided.

Here, as for the material of the front side resin layer 42, aninsulating material, for example, a resin material, such as an epoxy,polyimide, cyanate ester, Teflon (registered trademark), etc. forprinted circuit boards can be used.

FIGS. 9A and 9B are outline views after the fifth process and after thesixth process respectively. Also, FIG. 9 and the above-stated processdiagrams (FIG. 8A˜8C) do not strictly correspond. The point of view thatshould be understood in FIG. 9 is the mounted state of the electroniccomponents to a “cavities” formed in the core member 41 and the sealedstate by means of a resin (front side resin layer 42). Accordingly, asshown in FIG. 9, the electronic component 105˜107 (equivalent to theelectronic component 48˜51 of FIG. 8) are mounted correspondingly ineach of the cavity 93˜95 formed in the core member 41. The core member41 in the state whereby the electronic components 105˜107 are mounted iscompletely encapsulated by a resin 108 (equivalent to the front sideresin layer 42 of FIG. 8). In FIG. 9B, for convenience of the diagram,the sides of the core member 41 after encapsulating by a resin 108 areexposed. The sides are also actually covered completely by the resin108.

(Seventh Process: FIG. 10A)

Next, the thin film 90 is patterned. By this patterning, the heatdissipation pattern 83 for dissipating direct heat to the thin film 90via thermally conductive resin 55 among the electronic component 48, 51which require heat dissipation countermeasures is formed. That is,etching of the thin film 90 is performed so that the heat dissipationpattern 83 remains.

(Eighth Process: FIG. 10B)

Next, the groove 109˜125 are made in each of the front side resin layer42 and the rear side resin layer 43. For example, after partiallyremoving each class of resin by a Carbon Dioxide (CO2) gas laser, UltraViolet (UV) laser or excimer laser, etc., a groove 109˜125 is formed byremoving the residual substance of the resin by permanganic acid, plasmaashing, etc.

(Ninth Process: FIG. 10C)

Next, coppering and etching are performed to the groove 109˜125, anelectrode 62˜75 for performing the interlayer electric connection withterminals of the electronic component 48˜49, an electrode 58˜61 forcarrying out interlayer connection through the core member 41, etc. areformed. When necessary, in order to ensure the best adhesion of a resinand plating copper, the resin front surface may be roughened bypermanganic acid, etc. and enhancement processing of the surface areasmay be performed. Also, 126˜154 are an electrode or a circuit patternwhich are formed in each exposed surface of the front side resin layer42 and the rear side resin layer 43. The intermediate layer A in FIG. 5is produced by this tenth process.

(Tenth Process: FIG. 10D)

Next, the upper rank layer B and the lower rank layer C in FIG. 5 areformed by lamination in resin of each of the front side resin layer 42and the rear side resin layer 43 and by forming a necessary solderresist pattern for the front and rear of those resin.

FIGS. 11A and 11B are outline views after the tenth process whichillustrates an upper surface side perspective view and an undersideperspective view respectively. The point of view that should beunderstood in FIG. 11 is the upper rank layer B is laminated on theintermediate layer A and the lower rank layer C is laminated under theintermediate layer A. Also, the necessary electric conductivity pattern155˜170 formed in the exposed surface of the upper rank layer B and thelower rank layer C should be understood. Those which are positioned inthe exposed surface of the lower rank layer C among the electricconductivity pattern 155˜170 and has the greatest area (electricconductivity pattern 166) is used as a heat dissipation pattern fordissipating the heat of the electronic component 48 and 51.

The module 50 shown in FIG. 5 is completed by attaching necessarysurface mount components (electronic component 78˜82 of FIG. 5) afterperforming the above processes and attaching a cover 40 a when needed.

The module 40 which has such a structure has the following results.

(1) Since the plate-like core member 41 consisting of material (Cu,Alloy 42, Invar, etc.) having excellent electric conductivity, excellentheat conductivity and high rigidity is constituted as a base, bendingstress of the substrate can be minimized with the rigidity of the coremember 41 and substrate deformation which is not preferred can beavoided or controlled. Therefore, since conventional reinforcement(glass cloth) in the core member 41 is not needed, the exceptionaleffect of not producing associated problems related to the glass cloth(Notably, the problem of ion migration and the problem of the increasedmanufacturing cost accompanying the glass cloth cutting process at thetime of cavity shaping.) is acquired.

(2) Since the “island” shaped sections are not removed when the columnsegments are formed in a needed section wherein a resin (rear side resinlayer 43) is affixed on one side (embodiment rear surface) of the coremember 41, these can be used as the island-shaped section 56, 57 (columnsegments). Then, the electrical signal transmission paths and powersupply transmission paths between layers can easily be constituted viathe island-shaped sections 56, 57 and simplification of the modulardesign can be achieved.

(3) A cavity (bottomless hole 44˜47) can be formed in the core member21, as well as the electronic components 48˜51 can be readily embeddedin the cavity and high density packaging of the substrate can beconjointly improved with surface mounting.

(4) When an electronic component with a short height size or tall heightsize is embedded, a height size adjustment member 54 is inserted or ahole in the rear side resin layer is used. The height size of electroniccomponents can be readily adjusted and set properly so that the uppersurface height position of an electronic component does not exceed theupper surface height position of the core member 41. For this reason, itcan respond to loading at the time of manufacturing the compositemulti-layer substrate and breakage of the electronic components can beprevented.

(5) When dissipating the heat of the electronic components, the coremember 41 can be used for a heat dissipation path or a heat dissipationpattern (electrode pattern 166 of FIG. 11B) formed in the exposedsurface of the lower rank layer C can be used for heat dissipation.Especially the electronic component 48, 51 which generate a large amountof heat can be used in the module 40 constituted by embedding and can beconsidered as a suitable object.

(6) Curvature of the substrate can be avoided or controlled to theintermediate layer A by making the intermediate rank layer A, upper ranklayer B and lower rank layer C into a substantially symmetricalstructure.

As set forth above, the advantages of the present invention will now beexplained.

The present invention comprises a core member having sufficient rigidityto, resolve and eliminate various inconveniences (Namely, aggravation ofelectrical properties by accompanying generation of ion migration andthe increased manufacturing cost accompanying the glass cloth cuttingprocess) that accompany the use of conventional art type glass cloth asa reinforcing fabric material.

The present invention comprises a core member having sufficient rigidityto resolve and eliminate various inconveniences (Namely, aggravation ofelectrical properties by accompanying generation of ion migration andthe increased manufacturing cost accompanying the glass cloth cuttingprocess.) that accompany the use of conventional art type glass cloth asa reinforcing fabric material.

According to the present invention, since the core member uses ametallic core material the desired rigidity can be ensured and thusmaking the glass cloth fabric no longer necessary, and further the coremember can be used also as an electrical signal path and as a heatdissipation path.

According to the present invention, the core member is entirely coveredby resin material and the core member is isolated from ambient air.Thus, deterioration by oxidization, etc. can be prevented and durabilitycan be improved.

According to the present invention, using other sections of the coremember and divided column segments can be used as a part of theelectrical signal transmission path or power supply voltage transmissionpath to the direction of the front and rear surfaces of the substrateand flexibility of the wiring design can be improved.

According to the present invention, the core member can be used as aheat dissipation path of electronic components, and especially in caseswhen embedding electronic components which generate a large amount ofheat can be considered as a suitable object.

According to the present invention, the upper surface height position ofelectronic components can respond to loading at the time ofmanufacturing the composite multi-layer substrate and breakage of theelectronic components can be prevented.

According to the present invention, the height relation betweenelectronic components and the core member can be adjusted and the uppersurface height position of the core member can be made higher than theupper surface height position of an electronic component.

According to the present invention, the height size adjustment memberused for the height size adjustment can be used also as a heatdissipation member.

According to the present invention, a module which has the effects ofthe present invention according to the claims can be produced.

While the present invention has been described with reference to thepreferred embodiments, it is intended that the invention be not limitedby any of the details of the description therein but includes all theembodiments which fall within the scope of the appended claims.

1. A composite multi-layer substrate comprising: a flat plate-like coremember formed of a material having electric conductivity, heatconductivity and high rigidity properties; a front side resin layercovering a front surface of said core member a rear side resin layercovering a rear surface of said core member; a bottomless hole formed insaid core member and said rear side resin layer penetrating a front andrear of said core member and a front and rear of said rear side resinlayer; an electronic component mounted in said bottomless hole, thethickness of the electronic component being equal to or larger than thethickness of said core member; and a height size adjustment memberinterposed among said electronic component and said core member and saidrear side resin layer.
 2. The composite multi-layer substrate accordingto claim 1, wherein said core member comprises a metallic core material.3. The composite multi-layer substrate according to claim 1, furthercomprising: a side surface resin layer which covers a side surface ofsaid core member; wherein said core member is entirely covered by saidside surface resin layer, said front side resin layer and said rear sideresin layer.
 4. The composite multi-layer substrate according to claim1, further comprising: a column segment which divides said core memberand penetrates said front and rear surfaces in a thickness direction ofsaid core member; and said column segment adapted to providing anelectrical signal transmission path or a power supply voltagetransmission path to the front and rear surfaces of said substrate. 5.The composite multi-layer substrate according to claim 1, wherein saidcore member is adapted to dissipating heat from an electronic componentthrough the inner wall of said bottomless hole when said electroniccomponent is mounted in said bottomless hole.
 6. The compositemulti-layer substrate according to claim 1, wherein the upper surfaceheight position of said electronic component after mounting in saidbottomless hole at least does not cross the upper surface heightposition of said core member.
 7. The composite multi-layer substrateaccording to claim 1, wherein said height size adjustment member isinterposed between the bottom of said electronic component when saidelectronic component height size is lower than the depth size of saidcore member mounted in said bottomless hole, wherein said height sizeadjustment member is adapted to adjusting a height of said electroniccomponent.
 8. The composite multi-layer substrate according to claim 7,wherein said height size adjustment member constitutes material whichhas heat conductivity.
 9. The composite multi-layer substrate accordingto claim 1, wherein said front side resin layer and said rear side resinlayer are layers formed uniformly by sealing said core member by saidresin.